What type of shock may not allow the heart rate to increase to compensate for hypoperfusion?

The shock that causes heart rate to increase and to compensate for hypoperfusion is neurogenic shock. This happens when the arteries has lost their ability in dilating and contraction that will lead of a drop in the blood pressure of the individual.

because the light is a great source of energy for the plants to survive. (i hope this )

estuaries are the partially enclosed coastal bodies of brackish water formed at the mouth of sea where river meets an ocean. it is a transition zone between river and sea water so estuaries are influenced to both marine environment such as tides, waves and to riverine such as flow of fresh water and sediments. the mixing of sea and fresh water provide high level of nutrients, making estuaries a high product habitats.

many estuaries suffers degradation from a variety of human activities like erosion from deforestation, overgrazing, overfishing, drainage and eutrophication.

so from the above statement answers will be

1. false as estuaries are formed due to both brackish and freshwater.

2.true, due to high productivity estuaries are breeding ground for many marine species.

3. direct and indirect activities of man that contribute to pollution and deposition of sediments.